Pivotal sash windows adapted for installation in a master frame of a sash window assembly are well-known. The sash window assembly typically has opposed, vertically extending guide rails to enable vertical reciprocal sliding movement of the sash window in the master frame while cooperatively engaged with the guide rails. The sash window has a top sash rail, a base and a pair of stiles cooperatively connected together at adjacent extremities thereof to form a sash frame, usually a rectangular frame. Typically, a pair of spaced tilt-latches are installed on, or in, opposite ends of the top sash rail.
Each tilt-latch is generally comprised of a housing having an outward end opening and a latch bolt disposed within the housing. A spring disposed within the housing generally biases the latch bolt through the outward end opening to engage the guide rails of the master frame. The latch bolt can have a control button to allow for actuation of the latch bolt. An operator can use his finger to engage the button and actuate the latch bolt wherein the latch bolt is retracted into the housing. The control button can take the form of a hollowed out portion to accommodate the operator's finger. Retraction of the latch bolt releases the latch bolt from the guide rail. When the latch bolts of the opposed tilt-latches are actuated simultaneously, the sash window can then be pivoted from the master frame.
One type of tilt-latch is called an internal tilt-latch. The internal tilt-latch is mounted in the top sash rail. The top sash rail is typically extruded and, therefore, is sometimes referred to as an extrusion. The top sash rail accommodates the tilt-latch substantially within the extrusion. Generally, the internal tilt-latch comprises a housing having a latch bolt which is actuated by a control button. The latch bolt of the tilt-latch extends from the housing and extrusion to engage the guide rail of the master frame. The top rail has an opening through its upper surface to allow access to the control button on the latch bolt. The internal tilt-latch is generally fixedly attached to the extrusion by screws. Typically, the screws pass through the top surface of the top rail to engage the internal tilt-latch. This type of mounting, however, is considered unsightly and typically requires an externally mounted control plate that covers the screws. The tilt-latch can also be screw-mounted wherein the screws pass through a bottom wall or intermediate wall of the extrusion, and similarly engage the internal tilt-latch. This type of bottom or side mounting, however, can interfere with the glass panes of the sash window and associated mounting and insulating materials. Additionally, if a screw-mounted, internal tilt-latch fails and requires replacement, the sash window may sometimes require disassembly to replace the tilt-latch. Furthermore, other types of hardware mountings such as pivot bars, sash locks, sweep locks, casement operators or vent stops can also require screw mountings which can experience similar drawbacks.
The present invention is provided to solve these and other problems.